Typewriter attachment



June 9, 1959 P. KORNQER TYPEWRITER ATTACHMENT 4 Sheets-Sheet 1 Filed April 12', 1957 INVENTQR PETER KORNER FIG. 28

AGENT 4 Sheet s-Sheet 2 June 1959 P. KORNER' TYPEWRITER ATTACHMENT Filed April 12, 1957 June 9 1959 P. KORNER 2,889,908

, TYPEWRITER' ATTACHMENT Filed April 12, 195"? I 4 Sheets-Sheet 3 FIG. 4

June 9, 1959 P. KORNER TYPEWRITER ATTACHMENT 4 Sheet-Sheet 4 Filed April 12, 1957 United States Patent TYPEWRITER ATTACHMENT Peter Kiirner, Stuttgart-Degerloch, Germany, assignor to International Business Machines Corporation, New York, N.Y., a corporation of New York "Application April 12, 1957, Serial No. 652,446 Claims priority, application Germany April 28, 1956 Claims. (Cl. 197-151) This invention relates to typewriters, and particularly to a special hectographic attachment thereto.

For preparing reproducible inverse originals on typewriters it is customary today to use ribbons impregnated with hectographic ink. The hectographic ribbon is guided on the reverse side of the sheet to be printed along the printing platen, and advanced step by step like the normal ink ribbon. Various devices are available for advancing a hectographic ribbon in typewriters, including devices in which the ribbon is stepped along on a type impression.

One manner in which this type of ribbon advancing is accomplished is by arranging the guide or feed rolls for the hectographic ribbon directly on the carriage and driving the wind-off or wind-up ribbon spool from the typewriter. Another technique for accomplishing hectographic ribbon advancement is through the use of ribbon advancement posts provided on the right and left sides or only on one side of the typewriter, thereby enabling the ribbon to be guided through the machine in one movement. Other techniques require numerous reversals as well as a special control drive for the feed and guide rolls. Furthermore, stepping of the hectographic ribbon may be achieved through the typewriter feed roll drive in conjunction with the type lever movement and the wind-off spool associated with the hectographic ribbon on a type impression, the ribbon remaining in its set up position on a functional or nonprinting movement of the printing carriage.

Existing hectographic ribbon advancing techniques generally utilize a plurality of rolls and diagonal guides. This increased number of rolls and guides does not lend itself to correct feeding of the hectographic ribbon, inasmuch as the inking of said ribbons smears very easily. Furthermore, the use of a separate drive of one or another spool for the hectographic ribbon naturally tends to augment the pull of the very thin paper ribbon.

Therefore, the principal object of this invention is to provide an improved device for accomplishing the uniform feeding of a hectographic ribbon in a printing machine.

Another object is to provide a detachable attachment for a typewriter for moving a hectographic ribbon independently of the typewriter drive system.

Still another object of this invention is to provide an auxiliary carriage that is engageable with a printing carriage for guiding and advancing a hectographic ribbon along the printing platen.

Other objects of the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings, which disclose, by way of examples, the principle of the invention and the best mode, which has been contemplated, of applying that principle.

- Fig. 1 shows a conventional typewriter with the inventive device in its inoperative position.

Fig. 2 is a diagrammatic view of the inventive device.

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Fig. 3 is a side elevation of the inventive device.

Fig. 4 is a planed view of one portion of the inventive device.

Fig. 5 shows a spool support with a take up means for the hectographic ribbon.

Fig. 6 is a sectional view of the wind-ofi and wind-up spools for the hectographic ribbon.

Fig. 7 shows the contact device operated by the ink ribbon lever arrangement of the typewriter.

Fig. 8 is a circuit diagram showing the electrical interrelationship between the inventive device and the typewriter.

Initially it must be understood that the inventive device is a self-contained structural unit which may be detachably mounted on any typewriter. Although the device may be employed with regard to any typewriter, it will be explained in connection with a conventional, commercially available electric typewriter. As the disclosed structural unit is actually independent of the typewriter and the latter undergoes no changes as a result of its mounting thereon, a special description of the typewriter as such is deemed unnecessary.

Applicants device for preparing copiable inverse originals, particularly in typewriters, through the use of a hectographic ribbon, comprises an upper and lower frame, an auxiliary carriage that is detachably engaged to the printing carriage, and two frictionally connected supply and receiving spools. On its travel from the supply or wind-ofif spool over the auxiliary carriage to the receiving or wind-up spool, the hectographic ribbon passes through a typewriter operated brake system which, on a type depression, detains the ribbon, after the latter has been advanced along the printing platen. The brake system detains the ribbon for the duration of one step and then releases it to provide an additional length of ribbon from the Wind-off spool.

With such an arrangement, the hectographic ribbon is moved independently of the typewriter drive system, and is subjected to a uniform pulling strain for the duration of one step of advancement. Due to the existing frictional connection between the two spools serving to take up and release the hectographic ribbon the wind-up spool is moved along when the ribbon is released from the wind-off spool, so that the length of hectographic ribbon released on the stepping movement of the carriage is wound up at the same time.

magnet that is mounted on the upper frame and another magnet that is fixed to the auxiliary carriage. Both magnets are controlled by acontact operated by the ink ribbon link arrangement. Energization of these magnets causes the normally closed brake, that is mounted on the upper frame, to open and the normally open brake, mounted on the auxiliary carriage, to close.

The inventive device may be removably mounted on a typewriter as a complete unit. To render the hectographic ribbon inoperative and thereby make the typewriter operative in the normal fashion, an upper frame with an auxiliary carriage, that is rockable about pivot studs, is connected to the lower frame of the device which is detachably arranged on a typewriter. The pivot studs are attached to adjustable support levers when it is desired to set up the hectographic ribbon with respect to the typewriter.

As shown in Fig. l the structural unit of this invention comprises broadly a lower frame 1 and an upper frame 2 with an auxiliary carriage 3. The lower frame is formed of two plates connected by two spacing rods. The plates of the lower frame, arranged at the right and left of the typewriter, are extended upwardly to the guide rails for the printing carriage of the typewriter,

and are removably attached to the latter by means of knurled screws 4.

The lower frame 1 carries the upper frame 2 with the auxiliary carriage 3 that is rockable about the pivot studs 5. The latter are attached to special support levers 6, which can be secured in their set up position by knurled screws 7. As a result of this variable adjustment of pivot studs 5, the hectographic ribbon that is guided over the auxiliary carriage may be adjusted with respect to the printing platen.

The side plates 8 (Fig. 3) of the upper frame 2 are connected by a U-shaped guide rail 9 and a tube 10 formed as a running axle. 1-) is also pivoted in the side plates 8 of the upper frame 2. On plates 8 are mounted two guide rolls 11 and 12 (Figs. 3, 4) each facing the other but at different levels. Additional guide and feed rools 14 (Fig. 4) for the hectographic ribbon are provided on the support bar 13 that is fastened to the two plates 8. The height of the two guide rolls 14 is determined by their association with the wind-off and wind-up spools for the hectographic ribbon.

A magnet controlled ribbon brake 15 (Fig. 2) is mounted next to the right-hand guide roll 14. This brake comprises substantially a stationary pad formed of an elastic material which is acted upon by brake shoe 16, as shown in Fig. 4. The brake shoe is rotatable, and is associated with a spring 17, which, when the brake is stationary, pushes the brake shoe 16 against the pad. Associated with the brake shoe is an armature 18 of a magnet 20. 7 Upon the energization of magnet 20, armature 13 is attracted for opening the brake.

Sup-port bar 13 also carries post 21 (Fig. 4) that receives the wind-off and wind-up spools for the hectographic ribbon. Below the spools there is arranged a cross-shaped run off lock 23, whose hooked ends prevent the ribbon from running oif the lower spool support 22 (Figs. 3, 6) on which the ribbon is placed. The lower spool support 22 is freely rotatable on post 21, and is stopped by a ribbon brake 24 (Fig. 2.) on the bottom side of post 21. Lower spool support 22 is provided with a catch 25 (Fig. 6) which engages a friction clutch 26 that cooperates with a spool support 27. In this way a driving connection is established between the two spool supports through friction clutch 26. This arrangement also permits a rotary movement of the upper spool support 27 when the lower support 22 is braked or stopped by the ribbon brake 24. As mentioned above, the lower support 22 receives the unused hectographic ribbon, whereas the upper spool support 27 accommodates the printed or used hectographic ribbon.

Arranged above spool support 27 is another spool support 31 which has a special take-11p device for the used hectographic ribbon. This ribbon take-up device (Fig. 5) comprises a plurality of segments 28. that operate on the principle of an iris diaphragm. These segments are bent at their outer ends, and are engaged by a central disc 29 that is under the pulling action of spring 30. The latter spring tends to lead the rotatably mounted segments 28 to their home positions to form a closed circuit. The central disc 29 may be moved in rotary fashion by handle 32 that is mounted above the spool support 31. The handle itself moves within a longitudinal slot of support 31 (Fig. 6). A second handle 33 is fixed to spool support 31 for increasing control cfficiency. Handle 33 is joined to a post 34, and forms a loose connection between the two spool supports 27 and 31. The circle formed by the bent portions of segments 28 may be reduced towards the inside by moving the two handles 32 and 33 against each other, in this way moving the segments over central disc 29 towards post 21 (Fig. 6).

A pair of segments 28 overlap for the purpose of clamping the hectographic ribbon in the take-up device. This overlapping position 34 (Fig. 5) is broken or opened as soon as the two handles 32 and 33, as disclosed above,

The housing cover 11 (Fig.

move the segments towards the center, in this way reducing the size of the circle formed by segments 28 and allowing the hectographic ribbon to come off. A recoil lock 35 (Figs. 3, 6) mounted on the square portion of post 21 is also associated with the take-up spool represented by supports 27 and 31. The recoil lock permits a circular movement of take-up spool only in one direction. The spool supports 27 and 31, which are arranged coaxially on post 21, are secured by knurled nut 36.

The auxiliary carriage 3 associated with the upper frame 2 is provided with a central, rearwardly extending support sheet 37 (Figs. 3, 4), which has a number of rollers 38 for guiding the auxiliary carriage. The rear rollers 38 (Fig. 3) slide on the tubular running axle 10, which is arranged between the two plates 8 of the upper frame 2, and the front rollers 38, which are attached to the bottom side of support 37, slide in the U-shaped guide reel 9. It is also noted that the support sheet 37 accommodates the paired reversing rolls 39 (Fig. 4).

A magnet-controlled, normally open ribbon brake is associated with the left pair of reversing rolls 39 (Fig. 4). This ribbon brake resembles the above-described brake 15 that is associated with guide roll 14. That is to say, it also has a brake shoe 40 and an elastic pad 41. However, whereas brake 15 is normally closed, the ribbon brake is normally open. Upon the energization of magnet 42, the ribbon brake is closed, thereby detaining the hectographic ribbon.

The frame of auxiliary carriage 3 also carries, on its right and left sides, rolls 43 (Figs. 2, 4) for guiding the hectographic ribbon. The auxiliary carriage is equipped with a special guide tape 44 (Fig. l) to improve the guidance of the hectographic ribbon and to protect the printing platen against dirt. In order to engage the auxiliary carriage 3 with the printing carriage of a typewriter, the auxiliary carriage is provided, on its right and left sides, with manually operable clamping devices 45 (Figs. 1, 3) that are attached to the platen axle behind the platen turning knob.

Reference to Fig. 8 will show that current is supplied to the two brake magnets 20 and 42 through a contact device 46 that is operated by a plunger 47 (Fig. 7) which is attached to the ink ribbon lever arrangement. After the closure of contact 46, current is made available via rectifier 48 and delay capacitor 49 to the series connected brake magnets 20 and 42. A contact 50, controlled by the cover 11, may be connected as shown in Fig. 8, and may serve to provide additional control for the operation of the brake magnets. The key controlled input switch and the motor shown in Fig. 8 constitute an integral part of the typewriter, and require no further explanation here.

So long as the hectographic ribbon attachment is not used, it may be rocked rearwardly after the desired disengagement of auxiliary carriage 3, as shown in Fig. 1. For operation, carriage 3 is rocked so that the guide assembly 44 is supported in front of the printing platen and behind the sheet to be printed on. The hectographic ribbon runs ofi? the reel that is placed on the lower spool support 22 (Fig. 6) of the feed or guide roll 14 (Fig. 2) lying on the same level, and through the stationary brake 15 to reversing rolls 11 that are mounted on the right side of upper frame 2. The hectographic ribbon is then guided towards the center of the auxiliary carriage 3 to the pair of rolls 39, and from there to the right hand reversing rolls 43. The ribbon is then carried on the front side of the auxiliary carriage to guide 44 (Fig. 1) along which it is fed, from right to left before the printing platen. After being printed the ribbon is then directed over the left-hand rollers 43 of the auxiliary carriage to the left pair of rolls 39. Between left rolls 39, the hectographic ribbon passes through brake 42. The ribbon is then delivered to the left reversing rolls 12 of the upper frame, after which it is directed over the guide roll 14 to the ribbon take-up device between the spool supports 27 and 31 (Fig. 6) and there the returning end of the hectographic ribbon is clamped in position.

In a normal typing operation, upon the actuation of one of the typing keys, a hectographic ribbon is advanced step by step with the printing carriage. The stepping motion is achieved in the following manner. Upon the actuation of a key, the ribbon lever arrangement is rendered operative and the plunger 47 (Figs. 7, 8)- which is attached to this lever, closes contact 46, which brings about the energization of brake magnets 15 and 42. In this way, the normally closed brake 15 is opened and the normally opened brake 42 is closed. Delay capacitor 49 in the brake magnet circuit maintains this condition of magnets 15 and 42 until a printing operation has been accomplished and the auxiliary carriage 3 has been advanced one step.

Because ribbon brake 42 has detained the hectographic ribbon and the normally closed ribbon brake 15 is open, the ribbon is moved a distance of one step of carriage advance. At the same time, the corresponding length of hectographic ribbon is taken off the wind-01f spool. The spool support with the take-up device for the printed hectographic ribbon is moved along on a release of the unused ribbon due to the existing frictional connection between the spool supports of the ribbon wind-off and wind-up. The outer diameter of the hectographic ribbon on the wind-off spool 22 is smaller than the inner diameter of the ribbon take-up device 28 (Fig. 6). The backlash that is developed between the two spools is taken up by the friction clutch, in this way balancing the pulling strain on the ribbon.

In the event that a non-printing key of the typewriter is operated, the ink ribbon lever remains undisturbed, thereby preventing contact 46 from being closed. The brake magnets 15 and 42 remain de-energized, maintaining ribbon brake 15 in the closed condition and ribbon brake 42 in the open condition. With ribbon brake 15 closed, the hectographic ribbon cannot be moved. On a movement of the printing carriage for non-printing purposes, the ribbon in the take-up device 28 is secured against any movement by means of backlash lock 35 that is provided for this purpose.

When the upper frame 2 is rocked upwardly, e.g. during the insertion of a new sheet to be printed on or for correcting printed data, the hectographic ribbon remains in its original position. The return of the upper frame into its operating position will cause the unused portion of the hectographic ribbon to be placed in readiness for printing.

To remove the used or printed hectographic ribbon, knurled nut 36 is removed from spool axle 21 and lifted by means of handles 32 and 33 of the spool support 31 (Fig. 5). As a result of pressing handles 32 and 33 together, the segment circle 25 is reduced in area, thereby releasing the printed ribbon and causing it to fall oif. Tensioning of newly inserted ribbon is accomplished by stopping the wind-off spool 22 by brake lever 24 (Fig. 2) and manually turning the uppermost spool support 31 until the desired tension is achieved.

While there have been shown and described and pointed out the fundamental novel features of the invention as applied to a preferred embodiment, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art, without departing from the spirit of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the following claims.

What is claimed is:

1. In a typewriter of the power driven type for preparing inverse originals by means of a ribbon saturated with ink, a frame, a printing carriage, a hectographic ribbon control mechanism comprising a means detachably engageable with said frame, an auxiliary carriage supported on said engageable means and engageable with said printing carriage, a first spool mounted on said engageable means for feeding said ribbon, a second spool mounted on said engageable means for receiving said ribbon, a friction clutch for connecting said two spools, rolls on said engageable means and said auxiliary carriage for guiding said ribbon, and a plurality of brakes mounted on both said engageable means and said auxiliary carriage for controlling the step by step advancement of said ribbon.

2. In a typewriter of the power driven type wherein type impressions are produced at a printing station, in reverse on the back of a sheet, by horizontally feeding a ribbon between a platen and a sheet, a frame and a printing carriage in said typewriter, a hectographic ribbon control mechanism comprising a lower frame that is engageable with the frame of said typewriter, an auxiliary carriage engageable with said printing carriage, an upper frame rockably mounted on said lower frame and carrying said auxiliary carriage, a first spool mounted on said upper frame for feeding said ribbon, a second spool mounted on said upper frame for receiving said ribbon, a friction clutch for connecting said spools, and a plurality of oppositely operated brakes mounted on said upper frame and said auxiliary carriage for detaining the hectographic ribbon for the duration of one step and then releasing the ribbon to provide an additional length of ribbon 'for the supply spool.

3. In a typewriter of the power driven type wherein type impressions are produced at a printing station in reverse on the back of a sheet by horizontally feeding a ribbon between a platen and a sheet, a printing carriage, a hectographic ribbon control mechanism comprising means detachably engageable' with said typewriter, an auxiliary carriage supported on said engageable means engageable with said printing carriage, means mounted on said engageable means for feeding said ribbon, means mounted on said e'ngageable means for receiving said ribbon, means frictionally connecting said ribbon feeding and ribbon receiving means, means mounted on said engageable means for guiding said hectographic ribbon, and means mounted on both said engageable means and auxiliary carriage for creating uniform tension of said ribbon during each step of advancement between said feeding and receiving means.

4. A mechanism for attachment to a power driven typewriter, having a frame and a printing carriage, for preparing inverse originals by means of a hectographic ribbon, comprising the combination of means engageable with the frame of said typewriter, an auxiliary carriage supported on said engageable means and engageable with said printing carriage, means rockably connected to said engageable means for carrying said auxiliary carriage, means mounted on said rockably connected means for feeding said ribbon, means mounted on said rockably connected means for receiving said ribbon, and means mounted on both said rockably connected means and said auxiliary carriage .for moving said ribbon between said feeding and receiving means independently of the typewriter drive. I

5. A mechanism for attachment to a power driven typewriter having a printing carriage for preparing type impressions at a printing station, in reverse on the back of a sheet, by horizontally feeding a ribbon between a platen and a sheet, comprising structural means engageable with said typewriter,-an auxiliary carriage supported on said structural means and engageable with the printing carriage of said typewriter, a first spool mounted on said structural means for feeding said ribbon, a second spool mounted on said structural means for receiving said ribbon, a friction clutch for connecting the two spools, a plurality of rolls on said structural means and said auxiliary carriage for guiding said ribbon between said first and second spools, and a brake system on said structural means and said auxiliary carriage for uniformly advancing the ribbon one step only after each printing operation.

6. The invention according to claim 5, wherein the brake system comprises a normally open brake, a normally closed brake, and a pair of magnets each controlling a brake, said magnets being operated during the depression of a printing key in said typewriter.

7. The invention according to claim 6, wherein said structural means comprises a lower frame that is detachably mounted on said typewriter and an upper frame rockably connected to said lower frame and carrying said auxiliary carriage.

8. The invention according to claim 7, wherein means that connect said upper and lower frames permit the correct adjustment of said hectographic ribbon with respect to said platen.

9. The invention according to claim 8, wherein said feeding and receiving spools are removably arranged in the upper frame in a plane parallel to the hectographic ribbon.

10. The invention according to claim 9, wherein said receiving spool comprises a plurality of segments in a circle and means for reducing the outer diameter of this circle for removing said ribbon.

References Cited in the file of this patent UNITED STATES PATENTS 2,240,578 Rumbutis May 6, 1941 2,425,967 Toggenburger Aug. 19, 1947 2,479,669 Brumhill Aug. 23, 1949 2,609,077 Schroder Sept. 2, 1952 

